Mechanical pencil



Aug. l, 1950 F. FERBER MECHANICAL PENCIL Filed July 3, 1947 PatentedAug. 1, 1950 UNITED STATE s PAT-eur OFFICE MECHANICAL PENCIL `IIrederlier,A Englewood, N. J. p s I Application July aisizsenamo.758,935 I'v .i fr (colza-17) i Claims.

My invention is an improvementin mechanical pencils of the type having amagazine to carry a supply of leads of the properlengtlfi,` and partsadapted to move each lead successively into position to protrude fromthe pencil, so that the latter can be employed for writing whenever theowner needs it for such a purpose.

An object of the inventionv is to `provide amechanical pencil of simplebut superior design, comprising relatively few parts that `can be easilyand inexpensively produced and readily assembled, and capable of smoothand certain actua-` tion; subjecting the leads tono breaking stressesand keeping them intactV and` `unbroken and otherwise `unimpaired asthey are moved .intoI place and caused to project at the tip of thepencil for their intended use. I

A further object is to` provide a mechanical pencil having a casing witha guidingltube for the leads,` said tube being of novelfform` andmounted in a bearing member thatrpermits reciprocating movementof thetube to feedl thelead to the point of the pencil,` and to return toitsstarting point; the tube and the bearing member being so shapedthatithey `can be `quickly joined but are afterwards virtuallyinseparable.` This construction facilitates the proper union of thevarious parts and the maintenance of the `unit in efficient serviceablecondition is thus assured.

The drawings show the preferred embodiment of my invention and thecharacteristics are clefined in the appended claims.` But thisdisclosure is explanatory only; and I doA not wish to be restricted tothe exact structural'details `herein set forth. In practice I may resort`to various minor alterations without deviating 'from the generalprinciple which underlies the construction and mode of operation, oromittingariy` of the essential features wherein theinventlon resides.

On the drawings:

Figure l is a section through the casing and inner parts of a mechanicalpencil in accordance with my invention.

Figure 2 is a similar view with the parts in different positions; and

Figure 3 is a separate view in section of the guide tube for the leads.

In the drawings, the numeral I indicates a cylindrical casing, having aremovable conical tip 2 at the :front end, this tip being attached tothe casing and held in place by any suitable means. Within the tube is amovable sleeve 3 which projects from the other extremity (not shown) ofthe casing I and contains the leads 4. One of these leads` representedat 5 is showniin the middle of` the casing projecting from the point ofthe tip*2. The sleeve 3 can beimoved inward by pressing on itsprojecting end to push the centralle'ad 5 so that its extremityprotrudes from the tip, so that it can be utilized for writing. y

The guiding tube for the central lead 5 is in` dicated at 6, One endhasa collar or flangeu'l, this end having a concave surface 8, which isenveloped by the innerend of the sleeve 3. `The bore 9 of the tube 6 isof sufficient sizetoreceive one of the leads `which are stored in thesleeve 3; and, because of the concave surface 8, one `of the leads willalways slip into line with the bore sand move into it. In the sides ofthe tube 3 are slots Ill, through which project jaws'` II', the functionthereof being to grip the central lead 5 and move it towards the tip 2in a manner ex-` plained below. At the end opposite the collar I thetube 6" has slots I2, opening throughsaidend, and permitting said end tobe transversely compressed tol a slight extent. At the same end the bore9 has inside teeth or serrations I3. i 1

The tip 2 has a counterbored recess III at its inner end, internallythreaded at I5 to engage and hold a hollow bearing member I6inoriefpiece, having a collar or flange I'I. Integral with. this memberor gland I6, which has a `central bore I8 through it,` are twosubstantially semicircular lugs I9 projectingup from the collar Il.``These lugs are separated from one another bys'mall spaces between theiropposing side edgesy-said spaces being of uniform width; and between theside edges the inner faces of the lugs are concave on the saine radiusas the bore Iii, forrninga continuation 20 thereof. The ends of theflugsIS remote from the collar I1 have inside projections or rims 2lpresenting interior shoulders 22. Alongtlie opposite edges the rims arecounterbcredor bevelled as indicated at'23. The tube 6 has opposedshoulders 24 and25 between the slots I0 and the end having the insideteeth I3. Between these shoulders the tube 6 is thinnest, and from theshoulder 25 to said end the tube is still thinner than between the slotsII] and collar 1. The extremity with the inside teeth I3 has the form ofan expanded head 26 with a bevelled end 21. This head is thicker thanthe inside diameter of the bore I8 in the gland I6; but it can be forcedbetween the counterbored rims 2 I' and through the bore I 8; the part ofthe tube 6 with the slots I2 then yielding till the contractile head orend 26 projects from the threaded end of the gland I6. This gland I6with the tube 6 is then inserted into the casing I; the threaded end ofthe gland projecting from the open end of the casing; and the tip 2 canthen be screwed upon the gland I6.

When the gland IB and the tube 6 are thus assembled, the internal rims20 are between the shoulders 24 and 25, and with these shoulders and theshoulders 2I limit the movement of the tube 6. Adjacent the collar 1 andtube 6 is snugly encircled by a ring 28 to which the resilient jaws IIare secured by their ends; and

encircling the jaws I I is a tubular slidable bush` ing 29 encircled bythe adjacent end of the sleevel. 3, and having a collar 3D between itsends abut" ting the inner extremity of said sleeve. Th'ej'a-ws projectfrom the end of the bushing beyond thel 4 the tube consisted of two ormore parts threaded to be screwed together, it would be weak and theparts could not be properly lined up. The lead would break, or part ofthe tube would become separated from the remainder thereof. Asillustrated and described, this tube is straight, strong, rigid, anddurable. The pencil is also easy and quick to assemble, as above stated;because to connect the ,tube 6 and the gland I6, the end 25 of the tubeis merely thrust past the chamfered edges 23. The length of the feed ofthe lead is nicely determined and limited; so that too much of the leaddoes not stick out' from the tip and collar 30, and their outer edges 3|diverge' from the axis of the casing I.

The inner surface of i."

the bushing at the adjacent end 32 flaressomewhat; so that, when thebushing 29 is pushed vtowards the tip 2, it squeezes the jaws II intogripping engagement with the lead l and feeds it towards the open end ofthe tip. Between the collar 39 and the collar I1 `of the gland I6aspring enlarged end 26 of the tube 6, the toothed por-'l tions betweenthe slots I2 constituting jaws like the jaws II; because the tube 5 ispushed up by the spring 33 acting on the bushing 29, which engages thering 28 and presses it against the collar 'I to draw the end 26 into theendof the gland I6; so that the teeth i3 bind the lead and hold it inreadiness for writing. When the sleeve 3 and bushing 29- are actuated tomove against the force of the spring 33, the ring 23 displaoes the tube'6 in the gland. I6 enough to release the jaws I3, because the ring 29exerts enough -friction on the tube 6 to move it slightly. Then 'thejaws II can feed the lead forward as required.

As stated above, the extremity of the sleeve 3 projects from the end ofthe lcasing opposite tip 3;l and the lead 5 is fed forward merely bypressing on this end with the linger. In the bore of the tip 2 is alining 34, with an enlarged inner end 35, snugly tting an enlarged partof said bore adjacent the recess I4 in the tip 2. This lining haslongitudinal slots 36 opening through the opposite extremity, andvexcept for the part 35, it fits the bore of the tip loosely, so that itwill grip the end of the lead 5 passing through it lightly, but yieldsufficiently so that'the lead will not be obstructed or retarded. Itterminates within the tip 2, and the opening at the point of the tip isjust large enough to pass the lead, bracing the lead all round itscircumference and diminishing the risk of breaking it oil?.`

- The structure set out above thus makes both the tube B and gland I6 aone-pieceunit, no part of which can get out of operative position. If

"loss'bjf breaking off of the lead is avoided.

1 -.laying described my invention, what I believe'to be new is:

f" 1. -A pencil'vhaving a casing, a bearing memberwithga bore through itin said casing, said member having lugs with opposed internalprojections, a guide tube in said bore, said guide tubeA havingop'posedexternal shoulders and lbeing `relatively thin between Vsaid shoulders,said projectionsbeing between said shoulders.

2 The vpencil according to claim 1, in which the'space between the lugsis substantially equal to the diameterofthe bore, and the tube has acontractile end thicker than said diameter.v

3. The pencil according to 'cla-imi, in which the space between the lugsis substantially equal to the diameter of the bore, and the tube has acontractile end thickerthan said diameter, said tube and saidmember'each being in one piece.

4. A'p'enfcil 'having a casing, a bearing with a. bore through it inlthe casing, said bearing having opposed lugs at one end, said lugshavingconcave inner surfaces spaced apartby a distance substantially equal tothe' diameter of the bore,'S aid lugs having opposed internal rimspresenting shoulders, a guide tube in said member, said tubehavingshouldersl and a relatively thin part between said shoulders, said rimsbeing between shoulders, and the tube having'an enlargedv to theshoulder `at'theremoteend of said thin portion.

- FRED FERBER.

vRIFRENCES CITED `'The following references are of record in the me 0f.,this-Date@ 5 UNITED STATES rA'rENTs v Number '1 -Name Date 1,865,992"Woelm July 5, 1932 2,049,965 ^Leistenschneider Aug. 4, 1936 2,179,835

Ward Nov. 14, 1939

